The Sonoma Rotary kiln appears to be supported by poured concrete. In the front of the picture, rails are supported by a poured concrete wall at floor level. The walls form pits where hot calcined ore drops and cools after being calcined in the kiln. In some cases, the pits were lined with steel.
The first band, positioned approximately 10′ down the length of the tube is supported on what appears to be a brick floor, one course higher than the poured concrete floor. The additional brick course plus fact the rollers are larger in diameter than the wheels that run on the rails would allow the kiln to be modeled at a slight angle from a horizontal position.
The second band approximately 40′ down the length of the tube is supported on a poured concrete pier that looks to be about 3′ off the floor. Taking away the effect of the brick course, the rise would appear to be roughly 1 inch for each foot of run.
The support on the far end includes the chimney and hopper. See the hopper and chimney page for more details. It is made up of brick and is high enough to fully surround the rotary kiln tube.
The floor itself appears to be a double layer of brick on top of the wood floor, supported by wood beams. Presumably, the purpose of the brick is to provide fire protection on the floor in the area of the kiln.
This image shows the kiln tube at the kiln hood end. The hood will be fabricated from the right piece 1 1/4″ code 40 PVC joiner. The two tires will be made up of narrow pieces like the piece in the middle. The rollers that will support the tires are just below the tire in this photo.